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Cocaine and hyoscyamine are two tropane alkaloids (TA) from Erythroxylaceae and Solanaceae, respectively. These famous compounds possess anticholinergic properties that can be used to treat neuromuscular disorders. While the hyoscyamine biosynthetic pathway has been fully elucidated allowing its de novo synthesis in yeast, the cocaine pathway remained only partially elucidated. Recently, the Huang research group has completed the cocaine biosynthetic route by characterizing its two missing enzymes. This allowed the whole pathway to be transferring into Nicotiana benthamiana to achieve cocaine production. Here, besides highlighting the impact of this discovery, we discuss how TA biosynthesis evolved via the recruitment of two distinct and convergent pathways in Erythroxylaceae and Solanaceae. Finally, while enriching our knowledge on TA biosynthesis, this diversification of the molecular actors involved in cocaine and hyoscyamine biosynthesis opens perspectives in metabolic engineering by exploring enzyme biochemical plasticity that can ease and shorten TA pathway reconstitution in heterologous organisms., (© 2023 Wiley-VCH GmbH.)

The tropane alkaloids (TAs) hyoscyamine and scopolamine function as acetylcholine receptor antagonists and are used clinically as parasympatholytics to treat neuromuscular disorders in humans. While TAs are synthesized in a small subset of plant families, these specialized metabolites are only accumulated in limited quantities in plant organs. The complex chemical structures of these compounds make their industrial production by chemical synthesis very challenging, Therefore, the supply of these TAs still relies on intensive farming of Duboisia shrubs in tropical countries. Many adverse factors such as climate fluctuations and pandemics can thus influence annual world production. Based on the landmark microbial production of the antimalarial semi-synthetic artemisinin, the Smolke group recently developed a yeast cell factory capable of de novo synthesizing hyoscyamine and scopolamine, thus paving the way for an alternative production of these compounds., (© 2020 Wiley-VCH GmbH.)

Introduction: The population is ageing. This trend is expected to cause an increase in the number of driver licenses among the elderly, and in their mobility. The effect of medications on driving capability may be significant., Objectives: To characterize the comorbidities among elderly patients involved in traffic accidents who were hospitalized at Beilinson Hospital and the psychotropic drugs taken prior to the accident, to assess the prevalence of anticholinergic drug load in this population and to examine its effect on clinical outcomes after the accident among the drivers., Methods: This is a retrospective cross-sectional study of the elderly over the age of 65, who were involved in a traffic accident between the years 2005-2015 (drivers and pedestrians) and were hospitalized. For each patient, a Charlson comorbidity index score was calculated and 3 months pre-accident drug dispensing data were extracted. The evaluation of the anticholinergic drug load for each patient was performed using the Anticholinergic Cognitive Burden (ACB) scale., Results: The study included 291 patients (98 drivers, 193 pedestrians). Pedestrians were injured more severely in comparison to the drivers' subgroup. The population received an average of 8.1 systemic drugs during the 3 months period prior to the accident. Approximately 36.7% were prescribed psychotropic medication (27.1%, 16.4% and 2.4% benzodiazepines, antidepressants and antipsychotics respectively); 32.3% had significant anticholinergic load (ACB score> 1). No significant differences were found in the prevalence of use of psychotropic drugs and/or ACB score between pedestrian and drivers or with post-accident clinical outcomes between drivers with high versus low anticholinergic drug load., Conclusions: The prevalence of psychotropic and anticholinergic drug burden is high among elderly involved in traffic accidents. Pre-accident anti-cholinergic drug load does not affect clinical outcomes after the accident. Elderly pedestrians are injured more severely than elderly drivers.

Anticholinergic burden has been widely studied in specific patient populations with specific conditions. However, the prevalence in the general population is poorly understood. This retrospective cross-sectional study was a nationwide database analysis of outpatient prescriptions of anticholinergic medications. The study was based on Slovenian health claims data of all outpatient prescriptions in 2018. Anticholinergic burden was evaluated using the Anticholinergic Cognitive Burden scale. Three age groups were analysed: children (≤18 years), adults (19-64 years) and older adults (≥65 years). Anticholinergic medications were prescribed to 29.8% of the participants; 7.6% were exposed to a clinically significant anticholinergic burden. The proportion of patients exposed to anticholinergic burden was highest in older adults (43.2%), followed by adults (25.8%) and children (20.7%). The most frequently prescribed medications with the highest anticholinergic activity were antipsychotics and medications for urinary diseases (42.8% and 40.2%, respectively). Medications with second highest activity were mostly antiepileptics (87.3%). Medications with possible anticholinergic activity included diverse therapeutic groups. Anticholinergic burden is highest in older adults but is also considerable among adults and children. Medications with anticholinergic activity belong to diverse therapeutic groups. Further research is needed on safe use of these medications in all age groups.

A new method of obtaining multifunctional pyrazoles by the reaction of 1,3-dipolar addition of tribenzylsulfonyliminochloride to polarophiles has been developed. This imine is obtained by reacting tribenzylamine with N-chlorobenzene sulfamide (chloramine-B). Regardless of the structure and composition of polarophiles, the cyclization reaction takes place in the presence of alkali in 6-8 h of boiling, which proves the activation of the methylene groups of tribenzylamine using the electron-withdrawing sulfonamide group. These novel derivatives were effective inhibitors of the α-glycosidase, butyrylcholinesterase (BChE), and acetylcholinesterase enzymes (AChE) with Ki values in the range of 0.45 ± 0.08-1.24 ± 0.27 µM for α-glycosidase, 6.04 ± 0.95-11.61 ± 2.84 µM for BChE, and 2.04 ± 0.24-4.23 ± 1.02 µM for AChE, respectively. The biological activities of the studied molecules against enzyme molecules were investigated by molecular docking calculations. The enzymes studied were AChE for ID 4M0E, BChE for ID 5NN0 BChE, and α-Glycosidase for ID 1XSI (α-Gly) respectively., (Copyright © 2019 Elsevier Inc. All rights reserved.)

The glycopyrrolate soft analog, SGM, designed to be easily hydrolyzed into the significantly less active zwitterionic metabolite, SGa, typifies soft drug that reduces systemic side effects (a problem often seen with traditional anticholinergics) following local administration. In this study, hydrolysis of 2R3'R-SGM, the highest pharmacologically active stereoisomer of SGM, was investigated in human and rat tissues. In both species, 2R3'R-SGM was metabolized to 2R3'R-SGa in plasma but was stable in liver and intestine. The half-life of 2R3'R-SGM was found to be 16.9 min and 9.8 min in human and rat plasma, respectively. The enzyme inhibition and stimulation experiments showed that plasma paraoxonase 1 (PON1) is responsible for the hydrolysis of 2R3'R-SGM in humans and rats. The PON1-mediated hydrolysis of 2R3'R-SGM was confirmed in the lipoprotein-rich fractions of human plasma. As PON1 is naturally attached to high-density lipoprotein, it might be absent in topical tissues where 2R3'R-SGM is applied, supporting its local stability and efficacy. The metabolic behavior of 2R3'R-SGM indicates that it is an ideal soft drug to be detoxified as soon as it moves into systemic circulation. Furthermore, the similarity of 2R3'R-SGM metabolism in humans and rats showed that the rat is a suitable animal for preclinical study., (Copyright © 2019 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.)

Parkinson's disease (PD) is a neurodegenerative disorder caused by the loss of nigral dopaminergic neurons innervating the striatum, the main input structure of the basal ganglia. This creates an imbalance between dopaminergic inputs and cholinergic interneurons (ChIs) within the striatum. The efficacy of anticholinergic drugs, one of the earliest therapy for PD before the discovery of L-3,4-dihydroxyphenylalanine (L-DOPA) suggests an increased cholinergic tone in this disease. The dopamine (DA)-acetylcholine (ACh) balance hypothesis is now revisited with the use of novel cutting-edge techniques (optogenetics, pharmacogenetics, new electrophysiological recordings). This review will provide the background of the specific contribution of ChIs to striatal microcircuit organization in physiological and pathological conditions. The second goal of this review is to delve into the respective contributions of nicotinic and muscarinic receptor cholinergic subunits to the control of striatal afferent and efferent neuronal systems. Special attention will be given to the role played by muscarinic acetylcholine receptors (mAChRs) in the regulation of striatal network which may have important implications in the development of novel therapeutic strategies for motor and cognitive impairment in PD., (Copyright © 2019. Published by Elsevier Ltd.)

Antipsychotics are often the first-line treatment for behavioral and psychological symptoms of dementia. However, the potential anticholinergic effects of antipsychotics could counteract the therapeutic effects of cholinesterase inhibitors used to treat dementia. We investigated the inhibitory effects of 26 antipsychotics on [N-Methyl- 3 H]scopolamine specific binding in mouse cerebral cortex. At 10 -5  M, chlorpromazine, levomepromazine, prochlorperazine, timiperone, zotepine, pimozide, blonanserin, olanzapine, quetiapine, and clozapine inhibited [N-Methyl- 3 H]scopolamine binding by > 45%. Furthermore, the pK i values of chlorpromazine, levomepromazine, zotepine, olanzapine, and clozapine overlapped with their clinically achievable blood concentrations. Therefore, the anticholinergic properties of these antipsychotics could attenuate the effects of cholinesterase inhibitors., (Copyright © 2019 The Authors. Production and hosting by Elsevier B.V. All rights reserved.)

Starting from vanillin, known four benzyl bromides with Br were synthesized. The first synthesis of natural product 3,4-dibromo-5-((methylsulfonyl)methyl)benzene-1,2-diol (2) and 3,4,6-tribromo-5-((methylsulfonyl)methyl)benzene-1,2-diol (3) and derivatives were carried out by demethylation, acetylatilation, oxidation and hydrolysis reactions of the benzyl bromides. Also, these compounds were tested against some important enzymes like acetylcholinesterase and butyrylcholinesterase enzymes, carbonic anhydrase I, and II isoenzymes. The novel bromophenols showed Ki values of in range of 53.75 ± 12.54-234.68 ± 46.76 nM against hCA I, 42.84 ± 9.36 and 200.54 ± 57.25 nM against hCA II, 0.84 ± 0.12-14.63 ± 3.06 nM against AChE and 0.93 ± 0.20-18.53 ± 5.06 nM against BChE. Induced fit docking process performed on the compounds inhibiting hCA I, hCA II, AChE, and BChE receptors. Hydroxyl group should exist at the aromatic ring of the compounds for inhibition of the enzymes. The moieties reported in this study will be useful for design of more potent and selective inhibitors against the enzymes., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Aim: To identify effective treatments and risk factors associated with death rattle in adults at the end of life., Background: The presence of noisy, pooled respiratory tract secretions is among the most common symptoms in dying patients around the world. It is unknown if "death rattle" distresses patients, but it can distress relatives and clinicians. Treatments appear unsatisfactory, so prophylaxis would be ideal if possible., Design: Quantitative systematic review and narrative summary following Cochrane Collaboration guidelines., Data Sources: CINAHL, MEDLINE, Health Source Nursing and Web of Science were searched for international literature in any language published from 1993 - 2016 using MeSH headings and iterative interchangeable terms for "death rattle"., Review Methods: Randomized controlled trials were appraised using the Cochrane Collaboration's tool for assessing risk of bias. Non-randomized studies were assessed using ROBINS-I tool for assessing risk of bias in non-randomized studies of interventions. Instances of treatment and risk were extracted and relevant key findings extracted in line with Cochrane methods., Results: Five randomized trials and 23 non-randomized studies were analysed. No pharmacological or non-pharmacological treatment was found superior to placebo. There was a weak association between lung or brain metastases and presence of death rattle, but otherwise inconsistent empirical support for a range of potential risk factors., Conclusions: Clinicians have no clear evidence to follow in either treating death rattle or preventing it occurring. However, several risk factors look promising candidates for prospective analysis, so this review concludes with clear recommendations for further research., (© 2018 John Wiley & Sons Ltd.)

Background Overactive bladder syndrome is a condition where one or more of the symptoms such as pollakiuria, urgent need to urinate, nocturia and urinary incontinence is observed. Its prevalence ranges between 7 and 27 % in men and 9-43 % in women. The role of a pharmacist is to educate the patient on medications administration scheme, and drug interactions with particular food or food components. Aim of the review To assess a potential impact of food and fruit juice on the pharmacokinetic and therapeutic effects of medications used in treating overactive bladder syndrome. This information will enhance pharmaceutical care and is vital and helpful for pharmacists counseling their patients. Method In order to gather information on interactions of medications employed in bladder dysfunctions, the English language reports published in the PubMed, Embase, Cochrane and CINAHL database over the years 1996-2015 were studied. Additionally, other resources, namely drugs.com, Medscape, UpToDate, Micromedex, Medical Letter, as well as Stockley Drugs Interaction electronic publication were included in the study. The analysis also covered product data sheets for particular medicinal products. Results Meals and the consumption of grapefruit juice were found to exert a diversified effect on the pharmacokinetics of drugs employed in overactive bladder syndrome therapy. Neither tolterodine, nor mirabegron interact with food and citrus fruit juice, whereas darifenacin, fesoterodine, oxybutynin and solifenacin do interact with grapefruit and others citrus fruit juice. The effects of such interactions may potentially be negative to patients. Trospium absorption is significantly decreased by food. Conclusion For selected medicines used in treating bladder dysfunctions food and grapefruit juice consumption may significantly affect efficacy and safety of the therapy. All information on the topic is likely to enhance the quality of pharmaceutical care., Competing Interests: Authors have no conflict of interest to report.

A sensitive and convenient high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) method was developed to determine levophencynonate and demethyl levophencynonate levels in human plasma simultaneously. Chromatographic separation was achieved on a SHIMADZU Shim-Pack XR C8 column and mass spectrometric analysis was performed by an API5000 mass spectrometer coupled with an electro-spray ionization (ESI) source in the positive ion mode. The MRM transitions of m/z 358.4→156.4 and 344.5→144.2 were used to quantify levophencynonate and demethyl levophencynonate, respectively. This analytical method was fully validated with specificity, linearity, lower limit of quantitation (LLOQ), accuracy, precision, stability, matrix effect and recovery. The linearity of this method were developed to be within the concentration ranges of 10-4000pg/mL for levophencynonate and 25-8000pg/mL for demethyl levophencynonate in human plasma. This method was used in a clinical study which was administrated with single oral dose for Chinese healthy subjects to investigate the pharmacokinetics of levophencynonate and demethyl levophencynonate., (Copyright © 2016 Elsevier B.V. All rights reserved.)

A sensitive and selective liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed to simultaneously quantify phencynonate (PCN) and its major metabolite N-demethyl phencynonate (DM-PCN) in human plasma. Following one-step liquid-liquid extraction, the analytes were separated on a reversed-phase C18 column. Methanol and 0.02% formic acid in 10 mM ammonium acetate (62:38, v/v) was used as isocratic mobile phase at a flow-rate of 0.3 mL/min. An API 5000 tandem mass spectrometer equipped with a Turbo IonSpray ionization source was used as the detector and was operated in the positive ion mode. Multiple reaction monitoring using the transition of m/z 358.4 → m/z 156.2, m/z 344.4 → m/z 142.2, and m/z 361.3 → m/z 159.2 was performed to quantify PCN, DM-PCN, and the internal standard (D3 -PCN), respectively. This approach showed a lower limit of quantification of 10 pg/mL and 25 pg/mL for PCN and DM-PCN in plasma, respectively. This sensitivity was at least 50-fold superior to previously reported ones and thus enabled the approach well applicable to low-dose pharmacokinetic studies. The intra- and inter-day precisions were less than 14.2 % at each QC level for both PCN and DM-PCN. The inter-day relative errors ranged from -1.9% to -4.9% for PCN, and from 0.6% to 6.4% for DM-PCN. As a proof of principle, the validated method was successfully applied to simultaneous quantification of circulating PCN and DM-PCN in healthy subjects after a single oral administration of 2 mg phencynonate hydrochloride pellet., (Copyright © 2015 John Wiley & Sons, Ltd.)

In this article, we review the downregulation of acetylcholinergic activity in schizophrenia and discuss the similarity and difference between Alzheimer's disease (AD) and schizophrenia in terms of acetylcholine (ACh) and anticholinergic activity (AA); then, we propose the use of cognition-enhancing therapy for schizophrenia. As ACh regulates an inflammatory system, when the cholinergic system is downregulated to a critical level, the inflammatory system is activated. We consider the possibility that AA appears endogenously in AD and accelerates AD pathology. This hypothesis can also be applied to schizophrenia. In fact, even before the onset of the disorder, in the prodromal phase of schizophrenia, cognitive dysfunction exists, and antibodies against astrocyte muscarinic-1 and muscarinic-2 receptors are present in the serum of patients with the paranoid type of schizophrenia. Then we noted that the prodromal phase in schizophrenia might correspond to the mild stage in AD and the acute phase to moderate stage concerning AA. We also think that we should enhance cognition in schizophrenia even in the prodromal phase because as mentioned above, downregulation of ACh is prominent in schizophrenia even in the prodromal phase., (© 2015 S. Karger AG, Basel.)

We have previously proposed a hypothesis in which we argue that anticholinergic activity (AA) appears endogenously in Alzheimer's disease (AD). Acetylcholine (ACh) controls both cognitive function and inflammation. Consequently, when the downregulation of ACh reaches critical levels, the inflammatory system is upregulated and proinflammatory cytokines with AA appear. However, factors other than downregulation of ACh can produce AA; even if ACh downregulation does not reach critical levels, AA can still appear if one of these other AA-producing factors is added. These factors can include neurocognitive disorders other than AD, such as delirium and Lewy body disease (LBD). In delirium, ACh downregulation fails to reach critical levels, but AA appears due to the use of medicines, physical illnesses or mental stress (termed 'AA inserts'). In LBD, we speculate that AA appears endogenously, even in the absence of severe cognitive dysfunction, for 2 reasons. One reason is that patterns of ACh deterioration are different in LBD from those in AD, with synergistic actions between amyloid and α-synuclein thought to cause additional or severe symptoms that accelerate the disease course. The second reason is that AA occurs through disinhibition by reduced cortisol levels that result from severe autonomic parasympathetic dysfunction in LBD., (© 2015 S. Karger AG, Basel.)

We previously proposed the hypothesis of endogenous anticholinergic activity (AA) in Alzheimer's disease (AD). According to this hypothesis, the downregulation of acetylcholine seen in AD is associated with upregulation/hyperactivity of N-methyl-D-aspartate receptor (NMDAR). The hyperactivation of NMDAR then induces inflammation, which, in turn, causes AA to appear endogenously. Based on this hypothesis, we commented that cholinesterase inhibitors (ChEIs) are 'preventative' therapy for AD and NMDAR antagonists are the true 'treatment' for AD. We also noted that ChEIs, such as donepezil, could treat delirium. Moreover, we proposed measuring serum anticholinergic activity in patients, particularly AD patients, in out-of-hospital pharmacies to monitor the anticholinergic burden for targeted treatment., (© 2015 S. Karger AG, Basel.)

In this article, we review and repropose our hypothesis of the endogenous appearance of anticholinergic activity (AA) in Alzheimer's disease (AD). First, we introduce our previous articles and speculate that, because acetylcholine (ACh) regulates both cognitive function and inflammation, downregulation of this neurotransmitter causes upregulation of the inflammatory system. AA then appears endogenously with the production of cytokines and the downregulation of ACh in AD. To support our hypothesis, we present a female AD patient whose AA was considered to occur endogenously through her AD pathology. Her serum anticholinergic activity (SAA) was positive at her first visit to our memory clinic, was negative at the 1-year and 2-year follow-up visits, and had become positive again by 3 years. We speculate that the initial positive SAA was related to her AD pathology plus mental stress, and that her SAA at 3 years was related to her AD pathology only. Consequently, we believe that 2 patterns of SAA positivity (and therefore AA) exist. One occurs when the downregulation of ACh reaches a critical level, and the other occurs with the addition of some other factor such as medication, induced illness or mental stress that causes AA to affect AD pathology. Finally, we consider the pharmacotherapy of AD based on the proposed hypothesis and conclude that cholinesterase inhibitors can be used to prevent rapid disease progression, whereas N-methyl-D-aspartate receptor antagonists should be reserved for the treatment of AD that is already in a stage of rapid progression. We also propose a staging schema for patients with AD., (© 2015 S. Karger AG, Basel.)

This prospective study was designed to investigate whether there is any association between gastrointestinal effects and pesticide residue exposure (as measured by metabolite levels in urine and faecal samples) in young children and to describe background levels of pesticide residues in samples from healthy children in the UK. Children (N=136) between the ages of 1.0 and 4.2 years were recruited. Of these, 107 provided background baseline samples and 26 provided samples when suffering from gastrointestinal symptoms. Urine samples (from all populations) were positive for (non-specific) carbaryl metabolite (urine 19/78, faeces 9/99), organophosphate metabolites (urine 103/135, faeces 47/111) and pirimicarb metabolite (urine 72/175, faeces 45/135). There were no statistically significant differences between samples from children when healthy or unwell. The urinary 95th percentile values for the healthy population of young children in this study were 31 nmol/l (carbaryl metabolite), 2156 nmol/l (total organophosphate metabolites) and 139 nmol/l (pirimicarb metabolite). In this study, samples from children suffering gastrointestinal symptoms were no more associated with anti-cholinergic pesticide metabolite levels or rotaviral infection than samples from healthy children. Background levels of anti-cholinergic pesticide metabolites in healthy UK children were in agreement with previously reported levels from the US and Germany., (Crown Copyright © 2013. Published by Elsevier GmbH. All rights reserved.)

Introduction: The clinical management of allergic diseases involves a number of drugs, most of which are extensively metabolized. This review aims to analyze the metabolism and the clinical implications of altered metabolism for these drugs., Areas Covered: The authors present an overview of current knowledge of the metabolism of: antihistamine drugs, glucocorticoids, inhaled β-2 bronchodilators, anticholinergics and other drugs used in allergic diseases, such as cromoglycate, omalizumab, montelukast and epinephrine. Polymorphic drug metabolism is relevant for chlorpheniramine, loratadine and montelukast. Inhibition of drug metabolism is relevant for loratadine, methylprednisolone, fluticasone, mometasone, triamcinolone or prednisolone. Polymorphic pre-systemic metabolism may be relevant to budesonide, fluticasone, beclomethasone, mometasone or salmeterol. The authors also discuss the current information on gene variations according to the 1,000 genomes catalog and other databases. Finally, the authors review the clinical implications of these variations with a particular regard to drugs used in the management of allergic diseases., Expert Opinion: Most drugs used in allergic diseases are extensively metabolized. Drug interaction or adverse reactions related to altered metabolism are relevant issues that should be considered in the management of allergic diseases. However, much additional research is required before defining pharmacogenomic biomarkers for the management of drugs used in allergic diseases.

Overactive bladder (OAB) is a common autonomic disorder due mostly to lesions in the micturition-inhibiting area (D1 dopaminergic pathway in the basal ganglia) in Parkinson's disease (PD) and dementia with Lewy bodies (DLB). anticholinergic drugs are the mainstay in the treatment of OAB. However, since 1997, anticholinergic adverse events on the cognitive function have been recognized. Drugs with less lipophilic, less permeable through the blood-brain barrier are the choice in the treatment of OAB in elderly neurologic patients.

Background: Delirium, a frequently occurring, devastating disease, is often underdiagnosed, especially in dementia. Serum anticholinergic activity (SAA) was proposed as a disease marker as it may reflect delirium's important pathogenetic mechanism, cholinergic deficiency. We assessed the association of serum anticholinergic activity with delirium and its risk factors in a longitudinal study on elderly hip fracture patients., Method: Consecutive elderly patients admitted for hip fracture surgery (n = 142) were assessed longitudinally for delirium, risk factors, and serum markers (IL-6, cortisol, and SAA). Using a sophisticated statistical design, we evaluated the association between SAA and delirium in general and with adjustments, but also the temporal course, including the events fracture, surgery, and potential delirium, individual confounders, and a propensity score., Results: Among elderly hip fracture patients 51% developed delirium, these showed more risk factors (p < 0.001), and complications (p < 0.05). Uncontrolled SAA levels (463 samples) were significantly higher in the delirium group (4.2 vs. 3.4 pmol/ml) and increased with delirium onset, but risk factors absorbed the effect. Using mixed-modeling we found a significant increase in SAA concentration (7.6% (95%CI 5.0-10.2, p < 0.001)) per day, which was modified by surgery and delirium, but this effect was confounded by cognitive impairment and IL-6 values. Confounder control by propensity scores resulted in a disappearance of delirium-induced SAA increase., Conclusions: Delirium-predisposing factors are closely associated with changes in the temporal profile of serum anticholinergic activity and thus neutralize the previously documented association between higher SAA levels and delirium. An independent relationship of SAA to delirium presence is highly questionable., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Overactive bladder (OAB) is a common condition, particularly in the elderly. Anticholinergic agents are the mainstay of pharmacological treatment of OAB; however, many anticholinergics can cross the blood-brain barrier (BBB) and may cause central nervous system (CNS) effects, including cognitive deficits, which can be especially detrimental in older patients. Many anticholinergics have the potential to cause adverse CNS effects due to muscarinic (M(1)) receptor binding in the brain. Of note, permeability of the BBB increases with age and can also be affected by trauma, stress, and some diseases and medications. Passive crossing of a molecule across the BBB into the brain is dependent upon its physicochemical properties. Molecular characteristics that hinder passive BBB penetration include a large molecular size, positive or negative ionic charge at physiological pH, and a hydrophilic structure. Active transport across the BBB is dependent upon protein-mediated transporter systems, such as that of permeability-glycoprotein (P-gp), which occurs only for P-gp substrates, such as trospium chloride, darifenacin and fesoterodine. Reliance on active transport can be problematic since genetic polymorphisms of P-gp exist, and many commonly used drugs and even some foods are P-gp inhibitors or are substrates themselves and, due to competition, can reduce the amount of the drug that is actively transported out of the CNS. Therefore, for drugs that are preferred not to cross into the CNS, such as potent anticholinergics intended for the bladder, it is optimal to have minimal passive crossing of the BBB, although it may also be beneficial for the drug to be a substrate for an active efflux transport system. Anticholinergics demonstrate different propensities to cross the BBB. Darifenacin, fesoterodine and trospium chloride are substrates for P-gp and, therefore, are actively transported away from the brain. In addition, trospium chloride has not been detected in cerebrospinal fluid assays and does not appear to have significant CNS penetration. This article reviews the properties of anticholinergics that affect BBB penetration and active transport out of the CNS, discusses issues of increased BBB permeability in patients with OAB, and examines the clinical implications of BBB penetration on adverse events associated with anticholinergics.

Hyoscyamine and scopolamine tropane alkaloids found in several solanaceous plants are anticholinergic drugs. Hyoscyamine 6β-hydroxylase (H6H) catalyzes two consecutive oxidation reactions. The first reaction is the hydroxylation of hyoscyamine to 6β-hydroxyhyoscyamine and the second is epoxidation of 6β-hydroxyhyoscyamine yielding scopolamine that is the final metabolite in the tropane alkaloid biosynthetic pathway. The effects of trivalent chromium as KCr (SO4)(2) on the production of tropane alkaloids and the expression of hyoscyamine 6β-hydroxylase gene (h6h) were studied in micro-propagated Atropa belladonna L. plantlets. The results showed that chromium treatment decreased the growth parameters (weights and lengths of the plantlets) and chlorophyll contents and increased proline contents. Moreover, semiquantitave RT-PCR analysis showed that the transcript level of H6H increased under chromium treatment. This treatment also increased hyoscyamine and scopolamine contents as shown by HPLC analysis. Changes of scopolamine contents correlate with the expression levels of h6h gene under different concentrations of chromium., (Copyright © 2011 Elsevier Masson SAS. All rights reserved.)

Novel pharmacological strategies are aimed at the resolution of systemic inflammation in COPD potentiating peripheral blood T-cell (PBT-cell) apoptosis. Although muscarinic acetylcholine receptors (mAChRs) M(3) and choline-acetyltransferase (ChAT) participate in the airway inflammation of COPD, their role in PBT-cell apoptosis remains unexplained. We evaluated in PBT-cells from COPD patients, smoker (S) and control (C) subjects: (1) apoptosis (by annexin V binding), (2) mAChR M(3) and ChAT expression, acetylcholine (ACh)-binding; (3) choline levels in serum and PBT-cells extracts. We tested the effects of Tiotropium (Spiriva(®)) and hemicholinium-3 (HCh-3) on apoptosis, NFκB pathway, caspases 3 and 8 activity and choline levels, in PBT-cells from COPD patients. We showed that: (1) apoptosis, mAChR M(3) and ChAT expression and the CD3+ and CD8+ ACh-binding are increased in PBT-cells from COPD patients when compared to C subjects, while CD4+/CD8+ ratio of ACh-binding to PBT cells was reduced in COPD; (2) choline levels are higher in serum and PBT-cells extracts from COPD patients than in S and C; (3) Tiotropium and HCh-3 reduced CD4+ and increased CD8+ apoptosis via caspases 3 and 8 activities and via IκB mediated mechanisms in COPD patients. This study suggests the involvement of non-neuronal components of cholinergic system in the regulation of PBT-cell apoptosis in COPD and demonstrates that Tiotropium regulates CD4+ and CD8+ PBT-cell apoptosis. It provides novel putative pharmacological targets for the resolution of systemic inflammation in COPD., (Copyright © 2011 Elsevier GmbH. All rights reserved.)

The mainstay of pharmacological treatment of overactive bladder (OAB) is anticholinergic therapy using muscarinic receptor antagonists (tertiary or quaternary amines). Muscarinic receptors in the brain play an important role in cognitive function, and there is growing awareness that antimuscarinic OAB drugs may have adverse central nervous system (CNS) effects, ranging from headache to cognitive impairment and episodes of psychosis. This review discusses the physicochemical and pharmacokinetic properties of OAB antimuscarinics that affect their propensity to cause adverse CNS effects, as observed in phase III clinical trials and in specific investigations on cognitive function and sleep architecture. PubMed/MEDLINE was searched for "OAB" plus "muscarinic antagonists" or "anticholinergic drug." Additional relevant literature was identified by examining the reference lists of papers identified through the search. Preclinical and clinical trials in adults were assessed, focusing on the OAB antimuscarinics approved in the United States. The blood-brain barrier (BBB) plays a key role in protecting the CNS, but it is penetrable. The lipophilic tertiary amines, particularly oxybutynin, are more likely to cross the BBB than the hydrophilic quaternary amine trospium chloride, for which there are very few reports of adverse CNS effects. In fact, in 2008 the US product labels for oral oxybutynin were modified to include the potential for anticholinergic CNS events and a warning to monitor patients for adverse CNS effects. Even modest cognitive impairment in the elderly may negatively affect independence; therefore, selection of an antimuscarinic OAB drug with reduced potential for CNS effects is advisable., (© 2011 Blackwell Publishing Ltd.)

The parasympathetic branch of the autonomic nervous system regulates the activity of multiple organ systems. Muscarinic receptors are G-protein-coupled receptors that mediate the response to acetylcholine released from parasympathetic nerves. Their role in the unconscious regulation of organ and central nervous system function makes them potential therapeutic targets for a broad spectrum of diseases. The M2 muscarinic acetylcholine receptor (M2 receptor) is essential for the physiological control of cardiovascular function through activation of G-protein-coupled inwardly rectifying potassium channels, and is of particular interest because of its extensive pharmacological characterization with both orthosteric and allosteric ligands. Here we report the structure of the antagonist-bound human M2 receptor, the first human acetylcholine receptor to be characterized structurally, to our knowledge. The antagonist 3-quinuclidinyl-benzilate binds in the middle of a long aqueous channel extending approximately two-thirds through the membrane. The orthosteric binding pocket is formed by amino acids that are identical in all five muscarinic receptor subtypes, and shares structural homology with other functionally unrelated acetylcholine binding proteins from different species. A layer of tyrosine residues forms an aromatic cap restricting dissociation of the bound ligand. A binding site for allosteric ligands has been mapped to residues at the entrance to the binding pocket near this aromatic cap. The structure of the M2 receptor provides insights into the challenges of developing subtype-selective ligands for muscarinic receptors and their propensity for allosteric regulation.

Urolithiasis remains a very common disease in Western countries. Seventy to eighty percent of kidney stones are composed of calcium oxalate, and minor changes in urinary oxalate affect stone risk. Intestinal oxalate secretion mediated by anion exchanger SLC26A6 plays a major constitutive role in limiting net absorption of ingested oxalate, thereby preventing hyperoxaluria and calcium oxalate urolithiasis. Using the relatively selective PKC-δ inhibitor rottlerin, we had previously found that PKC-δ activation inhibits Slc26a6 activity in mouse duodenal tissue. To identify a model system to study physiologic agonists upstream of PKC-δ, we characterized the human intestinal cell line T84. Knockdown studies demonstrated that endogenous SLC26A6 mediates most of the oxalate transport by T84 cells. Cholinergic stimulation with carbachol modulates intestinal ion transport through signaling pathways including PKC activation. We therefore examined whether carbachol affects oxalate transport in T84 cells. We found that carbachol significantly inhibited oxalate transport by T84 cells, an effect blocked by rottlerin. Carbachol also led to significant translocation of PKC-δ from the cytosol to the membrane of T84 cells. Using pharmacological inhibitors, we observed that carbachol inhibits oxalate transport through the M(3) muscarinic receptor and phospholipase C. Utilizing the Src inhibitor PP2 and phosphorylation studies, we found that the observed regulation downstream of PKC-δ is partially mediated by c-Src. Biotinylation studies revealed that carbachol inhibits oxalate transport by reducing SLC26A6 surface expression. We conclude that carbachol negatively regulates oxalate transport by reducing SLC26A6 surface expression in T84 cells through signaling pathways including the M(3) muscarinic receptor, phospholipase C, PKC-δ, and c-Src.

Administration of drugs directly into the respiratory tree first was proposed a long time ago. Surfactant is the paradigmatic example of such therapies. Many other drugs have been used in the same way and further compounds are under investigation for this aim. In the last two decades, despite the wide number of drugs available for direct lung administration in critical care patients, few controlled data exist regarding their use in neonates and infants. This review will focus on drugs clinically available in a critical care setting for neonates and infants, including bronchodilators, pulmonary vasodilators, anti-inflammatory agents, mucolytics, resuscitative anti-infective agents, surfactants and other drugs. We provide an evidence-based comprehensive review of drugs available for intratracheal administration in paediatric and neonatal critical care and we examine possible advantages and risks for each proposed indication.

Ipratropium bromide (ipratropium) and tiotropium bromide (tiotropium), anticholinergic agents with bronchodilating properties, are used to treat patients with chronic obstructive pulmonary disease. Because they are actively secreted into urine, the interaction of these agents with organic cation transporters (OCTs/Octs) was examined in rat kidney slices and in cultured cells expressing rat Oct (rOct) or human OCT (hOCT). Uptake of radiolabeled ipratropium in rat kidney slices was significantly inhibited by OCT/Oct substrates including cimetidine, imipramine, and quinidine, but not by organic anion transporter substrates (e.g., p-aminohippuric acid and estrone-3-sulfate). [(3)H]Tiotropium uptake showed similar characteristics. Reverse transcription-polymerase chain reaction showed that, in rat kidney, mRNA expression of rOct2 was the highest, followed by rOct1, but little rOct3 was detected. In vitro, rOct1 and rOct2 transported both anticholinergics, but rOct3 accepted only ipratropium. Ipratropium uptake by rat kidney slices consisted of two components with K(m) values of 0.114 ± 0.06 and 24.5 ± 2.21 μM. The K(m) value of rOct2-mediated ipratropium uptake (0.143 ± 0.03 μM) was consistent with that of the high-affinity component. The OCT/Oct inhibitor corticosterone, at a concentration of 1 μM (IC(50), 1.11 ± 0.20 μM for rOct2-mediated ipratropium transport), inhibited ipratropium by 18.4%, suggesting that rOct2 is involved in renal secretion of ipratropium. In a similar manner, ipratropium and tiotropium were taken up by cultured cells expressing hOCT1 and hOCT2 but not hOCT3. We conclude that OCT2/Oct2 plays a role in renal secretion of both anticholinergics in these species. Coadministration of these anticholinergics with cationic drugs recognized by OCT2/Oct2 may decrease renal clearance, resulting in increased systemic exposure.

Early studies have shown that some of diterpenoid alkaloids, found in highly toxic plants of the genera Aconitum and Delphinium, act at neuronal nicotinic acetylcholine receptors (nAChRs) and exhibit potent N-cholinolytic activity. In the current study, GA-MLRA and GA-PLS approaches have been used to build QSAR models to predict N-cholinolytic activity measured in vivo (blockade of neuromuscular conductivity, BNMC and third eyelid relaxing activity, TYRA) and in vitro (suppression of frog's abdominal straight muscles on acetylcholine, SAM) for a series of diterpenoid alkaloids. Random splitting of a data set (five trials in total) produced QSAR models of a good level of correlation between experimental in vitro/in vivo and calculated N-cholinolytic activity expressed as log(1/ED(50)) with following average statistical parameters: log BNMC (r(2) = 0.87, s = 0.14, q(2) = 0.82), log TYRA (r(2) = 0.80, s = 0.29, q(2) = 0.67), log SAM (r(2) = 0.84, s = 29, q(2) = 0.64). QSAR results suggest descriptors accounting for H-bond capability of molecules influence all three type of N-cholinolytic activity with additional contribution of steric and reactivity features as identified for TYRA and SAM data, respectively. The alkaloid-receptor complexes were further analyzed by means of AutoDock Vina docking program using the binding site of MLA complexed with AChBP (homolog of the ligand binding domain of nAChRs) as template. All compounds were shown to be well fitted in the binding pocket of native MLA with good correlation exhibited between their ED(50) and AutoDock Vina binding free energy. An analysis of the possible factors significant for the ligand recognition has been enhanced by comparative docking studies performed for structurally related lycoctonine-type alkaloids (lappaconitine and aconitine) that are known to bind to voltage-gated Na(+) channel, but not to nAChRs., (2010 Elsevier Masson SAS. All rights reserved.)

We characterized contribution of N-oxide metabolites [1-methyl-4-piperidyl diphenylpropoxyacetate N-oxide (M-1) and 1-methyl-4-piperidyl benzilate N-oxide (M-2)] to the binding of muscarinic receptors in relation to the pharmacokinetics of propiverine in rats. The in vitro muscarinic receptor binding activity of M-2 was equipotent to that of propiverine, whereas M-1 was much less active. After the oral administration of propiverine (24.8-248 micromol/kg), there was relatively selective and longer-lasting binding of muscarinic receptors in the rat bladder compared with the submaxillary gland as shown by a significant increase in the apparent dissociation constant (K(d)) for specific binding of [N-methyl-(3)H]scopolamine ([(3)H]NMS). In addition, the intravesical instillation of M-2 produced a significant increase in K(d) for specific [(3)H]NMS binding in the rat bladder. Extremely high concentrations of M-1 and M-2 were detected in plasma after the oral administration of propiverine. The concentration of unbound M-2 was much higher than that of M-1 and propiverine in the rat plasma. The sum of maximal plasma unbound propiverine equivalents (C(max)) after the oral administration of propiverine at doses of 24.8, 74.3, and 248 micromol/kg was 66.0, 303, and 509 nM, respectively. The sum of corresponding area under the time-concentration curve from 0 to 12 h was 194, 2123, and 4645 nM . h, respectively. In fact, the unbound concentration of M-2 comprised more than 90% of sum of unbound propiverine equivalents in the plasma. After oral treatment with propiverine, the bladder showed the highest concentration of M-2, indicating specific distribution of this metabolite into the target organ. Thus, M-2 may contribute greatly to the relatively selective and long-lasting occupation of bladder muscarinic receptors after oral administration of propiverine.

Scopolamine (hyoscine) is commonly used as an anticholinergic drug to relieve nausea, vomiting and dizziness of a motion sickness as well as recovery from anesthesia and surgery. Sucrase as a hydrolytic enzyme breaks down sucrose into its monomers, glucose and fructose. The aim of this study was to evaluate the effect of scopolamine on the activity and the structural changes of yeast sucrase. The results showed that binding of scopolamine to sucrase could inhibit the enzyme activity. A non-competitive inhibition was observed in different concentrations of scopolamine (0.6 to 3.6mM). The study by circular dichroism measurement in far-UV showed that the absolute enzyme exhibited a flat negative trough, indicating the presence of alpha-helices and beta-sheet structures in the enzyme. Binding of the inhibitor on the enzyme made a deeper trough at 218nm, suggesting the increasing of beta-sheet content of the enzyme. Fluorescence measurement showed that binding of scopolamine to free enzyme and enzyme-substrate complex increased the peak intensity at 350nm and also induced red shift. Our findings suggest that scopolamine binds to the location other than the active site of enzyme and that the binding causes structural changes and inhibits the enzyme activity.

The muscarinic receptor antagonist propiverine used for therapy of overactive bladder undergoes first pass metabolism, leading to several active metabolites, which affect muscarinic receptors and L-type Ca(2+) channels with different potencies. M-5, the major metabolite in blood, and M-6 can be synthesized as cis- and trans-isomers. We systematically investigated the pharmacodynamic profiles of the isomers on detrusor contractile function. In murine and porcine detrusor, the effects of the derivatives were examined on contractions induced by electric field stimulation (EFS), cumulatively increasing concentrations of carbachol or high KCl concentration. EFS contractions were concentration-dependently reduced by the M-5 and M-6 isomers although to a different extent. M-5(cis) was slightly more potent than M-5(trans), but the differences did not reach statistical significance. M-6(cis) was significantly more potent than M-6(trans). Responses to carbachol were antagonized by all compounds due to rightward shifts of the concentration-response curves, but only M-5(trans) also significantly reduced the maximum response. pK (B) values obtained with Schild plot analysis indicated slightly higher potency for M-6(cis) than M-6(trans). Ca(2+) influx-dependent contractions elicited by K(+) depolarization were less impaired by low concentrations of the M-6 isomers, but strongly suppressed by 100 microM of the M-5 isomers, suggesting an additional effect of the two M-5 isomers on Ca(2+) influx. All investigated isomers of M-5 and M-6 are biologically active in reducing detrusor contraction in animal tissue. While M-5( cis,) M-6(cis), and M-6(trans) possess surmountable or partially surmountable antagonistic properties at muscarinic receptors, M-5(trans) is a strong non-competitive antagonist. However, at higher concentration ranges, all four compounds seem to have additional effects on Ca(2+) influx.

Purpose: The use of anticholinergic antiparkinson drugs is almost exclusively confined to treating antipsychotic-induced extrapyramidal side effects (EPS). We investigated the prevalence of concomitant prescription of anticholinergics as a proxy for antipsychotic-induced EPS and compared variance in prevalence with differences in the assumed mechanisms of action of antipsychotics on central nervous system (CNS) transmitter systems (i.e., receptor drug-binding profiles). We paid special attention to potential differences between typical and atypical antipsychotics., Methods: Data were drawn from the Norwegian Prescription Database on sales of antipsychotic and anticholinergic antiparkinson drugs to a total of 57,130 outpatients in 2004. We assessed concomitant dispensations of antipsychotic and anticholinergic drugs and correlated the prevalence of concomitantly prescribed anticholinergics to previously assessed receptor-binding profiles of antipsychotics., Results: The concurrent use of anticholinergics varied between 0.4% and 26.0% for patients using a single antipsychotic agent. The prevalence of anticholinergic comedication was more than twice as high in patients using two or more antipsychotic drugs. Four typical antipsychotics (fluphenazine, zuclopenthixol, haloperidol, and perphenazine) were associated with higher concomitant use of anticholinergics than the rest. For the remaining 14 antipsychotic agents, the difference between typical and atypical antipsychotics was neither pronounced nor systematic. A high degree of D2-receptor antagonism and a high 5-HT2A/D2-receptor-affinity ratio coincided with the use of anticholinergics., Conclusions: The liability of antipsychotic drugs to cause EPS seemed to vary considerably and largely independently of the distinction between typical and atypical antipsychotics.

Phenthonium (Phen), a quaternary analog of hyoscyamine, is a blocker of muscarinic activity and an allosteric blocker of alpha(1)2betagammaepsilon nicotinic receptors. Specifically, Phenthonium increases the spontaneous release of acetylcholine at the motor endplate without depolarizing the muscle or inhibiting cholinesterase activity. This paper compares Phenthonium's effects on sympathetic transmission and on ganglionic nicotinic receptor activation. Neurotransmitter release and twitch of the rat vas deferens were induced either by electrical stimulation or by 1,1-dimethyl-4-phenylpiperazine (DMPP) activation of nicotinic receptors. Contractions independent of transmitter release were induced by noradrenaline and adenosine 5'-triphosphate (ATP). Phenthonium inhibited transmitter release and depressed twitch without changing the responsiveness to noradrenaline or ATP. Twitch depression did not occur after K(+)-channel blockade with 4-aminopyridine (4-AP) or charybdotoxin. DMPP had a similar effect, but high concentrations induced contraction of non-stimulated organs. Incubation of Phenthonium inhibited further DMPP twitch depression and non-competitively depressed the contractile responses elicited by DMPP. Furthermore, mecamylamine, but neither methyllycaconitine nor atropine, blocked the contraction elicited by DMPP. Phenthonium and DMPP are K(+)-channel openers that primarily inhibit sympathetic transmission. Contraction induced by DMPP was probably mediated by neuronal nicotinic receptor other than the alpha7 subtype. The blockade of DMPP contractile response was unrelated to Phenthonium's antimuscarinic or K(+)-channel opening activities. Since Phenthonium's quaternary chemical structure limits its membrane diffusion, the non-competitive inhibition of DMPP excitatory responses should be linked to allosteric interaction with neuronal nicotinic receptors that putatively qualify Phenthonium as a novel modulator of cholinergic synapses.

Objectives: To examine whether anticholinergic medications have effects on the level of cognitive function or cognitive decline in persons in their early to mid 60s., Methods: A randomly selected community-based sample of 2058 persons aged 60-64 at baseline was interviewed twice over four years. Anticholinergic medication use was determined from self-report medication data using the Anticholinergic Drug Scale. Cognition was assessed with the California Verbal Learning Test I (one trial), Digits Backwards, the Symbol Digit Modalities Test, the Mini-Mental State Exam and simple and choice reaction time. Persons meeting criteria for Mild Cognitive Impairment were identified in a clinical substudy. Mixed models adjusting for age, sex, self-rated depression and physical health, and total number of medications were used to analyse the data., Results: There was a significant main effect of anticholinergic group averaged across time for the Symbol Digits Modalities Test with poorer performance among anticholinergic medication users. Main effects for the other cognitive tests and mild cognitive impairment were non-significant. No time by anticholinergic group interactions were significant., Conclusions: This study suggests that exposure to anticholinergic medication is associated with lower level of complex attention in the young-old, but not with greater cognitive decline over time. Although the clinical significance of this is not clear, caution should be taken when prescribing medications with anticholinergic effects to older persons., ((c) 2008 John Wiley & Sons, Ltd.)

Aims: The present study was conducted to understand the role of 1,2-dilynoleoyl-sn-glycero-3-phosphocholine (DLPhtCho) in cognitive functions., Main Methods: Two-electrode voltage-clamp was made to Xenopus oocytes expressing rat alpha7 acetylcholine (ACh) receptors. Field excitatory postsynaptic potentials (fEPSPs) were monitored from the CA1 region of rat hippocampal slices. Water maze test was carried out to assess spatial learning and memory for rats., Key Findings: In the oocyte expression system, DLPhtCho at a concentration of 10 microM potentiated ACh-evoked currents to approximately 190% of basal amplitudes 70 min after 10-min treatment. In contrast, 1-stearoyl-2-lynoleoyl-sn-glycero-3-phosphocholine (SLPhtCho), 1-palmitoyl-2-linoleoyl-sn-glycero-3-phosphocholine (PLPhtCho), and 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPhtCho) had no effect on the currents. DLPhtCho (10 microM) enhanced slope of fEPSPs to about 150% of basal levels at 70-min treatment, that is inhibited by alpha-bungarotoxin, an inhibitor of alpha7 ACh receptors, while no enhancement was obtained with SLPhtCho, PLPhtCho, or POPhtCho. In the water maze test, oral administration with DLPhtCho (5 mg/kg) significantly shortened the prolonged acquisition latency for rats intraperitoneally injected with scopolamine (1 mg/kg)., Significance: The results of the present study show that DLPhtCho improves scopolamine-induced learning and memory deficits, possibly by facilitating hippocampal synaptic transmission under the control of alpha7 ACh receptors. DLPhtCho, therefore, could be developed as a beneficial anti-dementia drug.

Antiamnesic activity of Noopept was studied on the original three-way model of conditioned passive avoidance response, which allows studying spatial component of memory. Cholinoceptor antagonists of both types (scopolamine and mecamylamine) decreased entry latency and reduced the probability for selection of the safe compartment. Noopept abolished the antiamnesic effect of cholinoceptor antagonists and improved spatial preference.

Purpose: In this study, isomers of two N-substituted soft anticholinergics based on glycopyrrolate, SGM (PcPOAGP&#95;NA.Me) and SGE (PcPOAGP&#95;NA.Et) [3'-(2-cyclopentyl-2-phenyl-2-hydroxyacetoxy)-1'-methyl-1'-alkoxycarbonylpyrrolidinium bromide] and their zwitterionic metabolite, SGa (PcPOAGP&#95;NA.H) [3'-(2-cyclopentyl-2-phenyl-2-hydroxyacetoxy)-1'-methyl-1'-carboxymethylpyrrolidinium inner salt] were synthesized and their pharmacological activities were evaluated in vitro and in vivo., Methods: The isomers of SGM and SGE were synthesized with both optically pure methyl-cyclopentylmandelate and 3-hydroxy-N-methylpyrrolidine. Trans-esterification followed by quarternization with alkyl bromoacetate gave four isomers of SGM or SGE with the nitrogen chiral center unresolved (2R3'S-SGM, 2R3'R-SGM, 2S3'S-SGM, 2S3'R-SGM or 2R3'S-SGE, 2R3'R-SGE, 2S3'S-SGE, 2S3'R-SGE). The hydrolysis of these four isomers followed by HPLC separation resulted in eight fully resolved isomers of SGa (2R3'R1'R, 2R3'S1'R, 2R3'R1'S, 2R3'S1'S, 2S3'R1'R, 2S3'S1'R, 2S3'R1'S, and 2S3'S1'S). Pharmacological activities were assessed by using in vitro receptor-binding assay and guinea pig ileum pA2-assay, and by evaluating the in vivo rabbit mydriatic effects. Results were compared to those obtained with conventional anticholinergic agents, such as glycopyrrolate, N-meythylscopolamine, and tropicamide, as well as those obtained with previously prepared racemic mixtures and 2R isomers., Results: Receptor binding pKi values at cloned human muscarinic receptors (M1-M4 subtypes) were in the 6.0-9.5 range for the newly synthesized SGM and SGE isomers, and in the 5.0-8.6 range for the SGa isomers. In all cases, 2R isomers were significantly more active than 2S isomers (27 to 447 times for SGM isomers, and 6 to 4467 times for SGa isomers). Among the four SGM isomers with unresolved 1' (N) chiral center, the 3'R isomers were more active than the corresponding 3'S isomers (1.5-12.9 times), whereas, among the SGa isomers, the 3'S isomers were not always more active than the corresponding 3'R isomers indicating that activity determined based on configuration at chiral center 3' is significantly affected by the configuration of the other two chiral centers, 2 and 1'. Among the completely resolved eight SGa isomers (all three chiral centers resolved), 1'S isomers were always more active than the corresponding 1'R isomers (1.8-22.4 times). Results also indicate that some isomers showed good M3/M2 muscarinic-receptor subtype-selectivity (about 3-5 times), and 2R and 3'S were the determining configurations for this property. Guinea pig ileum assays and rabbit mydriasis tests on SGa isomers further confirmed the stereospecificity. In rabbit eyes, some 2R-SGa isomers showed mydriatic potencies similar to glycopyrrolate and exceeded tropicamide, but their mydriatic effects lasted considerably shorter, and they did not induce dilation of the pupil in the contralateral, water-treated eye. These results indicate that these compounds are locally active, but safe and have a low potential to cause systemic side effects. The pharmacological potency of the eight SGa isomers was estimated as 2R3'S1'S approximately equal to 2R3'R1'S approximately equal to 2R3'S1'R > 2R3'R1'R > 2S3'R1'S > 2S3'S1'S approximately equal to 2S3'R1'R > 2S3'S1'R (p < 0.05)., Conclusions: The stereospecificity and M3/M2 muscarinic-receptor subtype-selectivity of soft anticholinergics, SGM, SGE, and SGa have been demonstrated. In agreement with previous results, the potential for their effective and safe use has been confirmed.

Purpose: The objective of this study was to evaluate the influence of propiverine-HCl (P4) and propiverine-N-oxide (P4NO), one of the major metabolites of P4, on bladder contraction in a standardized in vivo model. Additionally, salivary flow measurements enabled the evaluation of hyposalivation, one of the most predominant anticholinergic side effects., Materials and Methods: Ten male mini pigs were anesthetized. P4 (0.4 mg/kg b.w.) and P4NO (0.422 mg/kg b.w.) were administered intravenously. Bladder contractions were induced through sacral anterior root stimulation and cystometrogram evaluation was performed. For stimulation-induced salivary flow measurements, the lingual nerve was exposed for neurostimulation. The effects of P4 and P4NO on stimulation-induced bladder contraction and salivation were evaluated in 5 mini pigs, respectively., Results: In all experiments, for each animal reproducible intravesical pressure values (Pves) were elicited during sacral anterior root stimulation before administration of the study drug. After administration of P4, Pves decreased by 64% whereas P4NO decreased Pves by 28%. Inhibition of salivary flow with P4 and P4NO was 71 and 32%, respectively. Directly following intravenous administration of P4, a short-term and reversible period of mild fluctuations in heart rate was observed. Administration of P4NO revealed no changes in either heart rate, or blood pressure., Conclusion: All of the investigated parameters revealed less anticholinergic effects for P4NO compared to P4. Under the experimental conditions described above, it may be assumed that P4NO behaves as a substance with poor anticholinergic effects with respect to side effects. As expected, P4 showed anticholinergic effects on bladder contraction and salivation.

Background: Smoking is the principle risk factor for development of chronic obstructive pulmonary disease (COPD). Multidrug resistance-associated protein 1 (MRP1) is known to protect against toxic compounds and oxidative stress, and might play a role in protection against smoke-induced disease progression. We questioned whether MRP1-mediated transport is influenced by pulmonary drugs that are commonly prescribed in COPD., Methods: The immortalized human bronchial epithelial cell line 16HBE14o- was used to analyze direct in vitro effects of budesonide, formoterol, ipratropium bromide and N-acetylcysteine (NAC) on MRP1-mediated transport. Carboxyfluorescein (CF) was used as a model MRP1 substrate and was measured with functional flow cytometry., Results: Formoterol had a minor effect, whereas budesonide concentration-dependently decreased CF transport by MRP1. Remarkably, addition of formoterol to the highest concentration of budesonide increased CF transport. Ipratropium bromide inhibited CF transport at low concentrations and tended to increase CF transport at higher levels. NAC increased CF transport by MRP1 in a concentration-dependent manner., Conclusions: Our data suggest that, besides their positive effects on respiratory symptoms, budesonide, formoterol, ipratropium bromide, and NAC modulate MRP1 activity in bronchial epithelial cells. Further studies are required to assess whether stimulation of MRP1 activity is beneficial for long-term treatment of COPD.

The purpose of the present study was to explore the passive and electrically assisted transdermal transport of diphenhydramine hydrochloride (DPH) by iontophoresis. For better bioavailability, better patient compliance, and enhanced delivery of DPH, an iontophoretic drug delivery system of a thermosensitive DPH gel was formulated using Lutrol F-127. The study was conducted using silver-silver chloride electrodes across hairless pig skin. The effects of pH, polymer concentration, electrode design, and pulse rate on the DPH permeation were investigated. The relationship between temperature, viscosity, and conductance of DPH was correlated using conductometry. Iontophoretic transport of DPH was found to increase with a decrease in the pH of the medium and an increase in the surface area of the electrode. Viscosity measurements and flux calculations indicated the suitability of the Lutrol gel for transdermal iontophoretic delivery of DPH. Anodal pulsed iontophoresis with disc electrode significantly increased the DPH skin permeation as compared with the passive controls.

MHP-133 is one of a novel series of compounds designed to target multiple brain substrates expected to have synergistic actions in the treatment of cognitive and neurodegenerative disorders such as Alzheimer's disease. The strategy was to develop compounds with multiple targets relevant for enhancing cognition and memory, but avoiding the serious side effects attributed to high potency cholinergic agonists. MHP-133 was shown to interact with subtypes of cholinergic, serotonergic, and imidazoline receptors and to weakly inhibit acetylcholinesterase activity. In vitro, the drug enhanced nerve growth factor (TrkA) receptor expression; it prevented excitotoxicity in a hippocampal slice preparation; and increased the secretion of soluble (non-toxic) amyloid precursor protein. MHP-133 also enhanced cognitive performance by rats and by non-human primate in tasks designed to assess working memory. The results of this study are consistent with the potential use of MHP-133 in the treatment of neurodegenerative disorders such as Alzheimer's disease.

Anticholinergic Drug Scale (ADS) scores were previously associated with serum anticholinergic activity (SAA) in a pilot study. To replicate these results, the association between ADS scores and SAA was determined using simple linear regression in subjects from a study of delirium in 201 long-term care facility residents who were not included in the pilot study. Simple and multiple linear regression models were then used to determine whether the ADS could be modified to more effectively predict SAA in all 297 subjects. In the replication analysis, ADS scores were significantly associated with SAA (R2 = .0947, P < .0001). In the modification analysis, each model significantly predicted SAA, including ADS scores (R2 = .0741, P < .0001). The modifications examined did not appear useful in optimizing the ADS. This study replicated findings on the association of the ADS with SAA. Future work will determine whether the ADS is clinically useful for preventing anticholinergic adverse effects.

Propiverine is a commonly used antimuscarinic drug used as therapy for symptoms of an overactive bladder. Propiverine is extensively biotransformed into several metabolites that could contribute to its spasmolytic action. In fact, three propiverine metabolites (M-5, M-6 and M-14) have been shown to affect various detrusor functions, including contractile responses and L-type calcium-currents, in humans, pigs and mice, albeit with different potency. The aim of our study was to provide experimental evidence for the relationship between the binding of propiverine and its metabolites to human muscarinic receptor subtypes (hM(1)-hM(5)) expressed in chinese hamster ovary cells, and to examine the effects of these compounds on muscarinic receptor-mediated detrusor function. Propiverine, M-5, M-6 and M-14 bound to hM(1)-hM(5) receptors with the same order of affinity for all five subtypes: M-6 > propiverine > M-14 > M-5. In HEK-293 cells expressing hM(3), carbachol-induced release of intracellular Ca(2+) ([Ca(2+)](i)) was suppressed by propiverine and its metabolites; the respective concentration-response curves for carbachol-induced Ca(2+)-responses were shifted to the right. At higher concentrations, propiverine and M-14, but not M-5 and M-6, directly elevated [Ca(2+)](i). These results were confirmed for propiverine in human detrusor smooth muscle cells (hDSMC). Propiverine and the three metabolites decreased detrusor contractions evoked by electric field stimulation in a concentration-dependent manner, the order of potency being the same as the order of binding affinity. We conclude that, in comparison with the parent compound, loss of the aliphatic side chain in propiverine metabolites is associated with higher binding affinity to hM(1)-hM(5) receptors and higher functional potency. Change from a tertiary to a secondary amine (M-14) results in lower binding affinity and reduced potency. Oxidation of the nitrogen (M-5) further lowers binding affinity as well as functional potency.

The polypeptide snake toxin alpha-bungarotoxin (BTX) has been used in hundreds of studies on the structure, function, and development of the neuromuscular junction because it binds tightly and specifically to the nicotinic acetylcholine receptors (nAChRs) at this synapse. We show here that BTX also binds to and blocks a subset of GABA(A) receptors (GABA(A)Rs) that contain the GABA(A)R beta3 subunit. These results introduce a previously unrecognized tool for analysis of GABA(A)Rs but may complicate interpretation of some studies on neuronal nAChRs.

Objective: The leaves of sage (Salvia officinalis L., Lamiaceae) are reported to have a wide range of biological activities, such as anti-bacterial, fungistatic, virustatic, astringent, eupeptic and anti-hydrotic effects. To determine the mnemogenic effect of sage leaves, we investigated the effects of ethanolic extract of sage leaves and its interaction with cholinergic system on memory retention of passive avoidance learning in rats., Methods: Post-training intracerebroventricular (i.c.v.) injections were carried out in all the experiments except ethanolic extract (i.p. intraperitoneally)., Results: Administration of ethanolic extract (50 mg/kg), pilocarpine (0.5 and 1 mg/rat), the muscarinic cholinoceptor agonist, and nicotine (0.1 and 1 microg/rat) increased, while mecamylamine (1, 5 microg/rat), the muscarinic cholinoceptor antagonist, and mecamylamine (0.01 and 0.1 microg/rat), the nicotine cholinoceptor antagonist decreased memory retention in rats. Activation of muscarinic cholinoceptors by pilocarpine potentiated the response of ethanolic extract. Also, pharmacological blockade of scopolamine attenuated potentiating effect of ethanolic extract. Activation of nicotinic cholinoceptor by nicotine potentiated the response of ethanolic extract. Blockade of nicotinic cholinoceptor by mecamylamine attenuated the response of ethanolic extract., Conclusion: It is concluded that the ethanolic extract of salvia officinalis potentiated memory retention and also it has an interaction with muscarinic and nicotinic cholinergic systems that is involved in the memory retention process.

The present study was undertaken to characterize in vivo muscarinic receptor binding of N-desethyl-oxybutynin (DEOB), active metabolite of oxybutynin (anticholinergic agent), in the bladder, submaxillary gland, heart and colon of rats, in relation to the plasma concentrations and inhibition of salivation. In the in vitro experiment, DEOB, as well as oxybutynin, inhibited the concentration-dependently specific [3H]N-methylscopolamine (NMS) binding in rat tissues and the affinity of DEOB in the rat bladder, submaxillary gland and colon was significantly (about 2 times) greater than that of oxybutynin. Following i.v. injection of DEOB (2.73-27.3 micromol/kg), there were dose- and time-dependent increases in the apparent dissociation constant (Kd) for specific [3H]NMS binding in the bladder, submaxillary gland, heart and colon of rats, compared with control values, and the effect was similar to that by i.v. injection of oxybutynin (2.54-25.4 micromol/kg). Plasma concentrations of DEOB and oxybutynin in these rats showed dose- and time-dependent increases. The pilocarpine-induced salivary secretion in rats was equipotently reduced by the i.v. injection of DEOB and oxybutynin. In conclusion, it has been shown that intravenously injected DEOB, as well as oxybutynin, binds significantly to muscarinic receptors in rat tissues including the bladder and salivary gland and the receptor binding activity of DEOB is roughly similar to that of oxybutynin.

The literature data devoted to endogenous allosteric regulators of membrane bound receptors are summarized in the present review. The allosteric processes are classified to (i) cooperative interaction, (ii) nonspecific, (iii) functional, and (iv) specific regulations according to target topography in a receptor. The specific endogenous allosteric regulators are described for GABAA, NMDA, muscarinic, nicotinic, serotonin, and opioid receptors. Substances of different chemical structure (peptides, lipids, and polycyclics) are able both to activate or inhibit binding and function of respective receptors. Some pathological processes appear to depend on endogenous receptor modulators. The role of the regulators is speculated in terms of receptor homeostasis, in particular, counteraction of receptor tolerance and/or sensitisation during physiological pulsation in a ligand' level in synaptic cleft.